It looks fine to me :) make sure if you add fish prone to jumping that you look into a cover for the tank. My filtration (using sump) is overflow - filter socks - skimmer - bag of active carbon (not always) - refugium with chaeto and live rock and rubble - return pump. In your tank I would put the sponge before the media. Consider adding some ceramic rings and dose some live copepods in that section. Give them some phytoplankton. They are really good at cleaning the tank.
for the moment it is a bit too early to add anything, so I would suggest to just keep it running with lights off for about 6 weeks or when cycle is completed